Fertagyl ® is indicated for the treatment of ovarian follicular cysts in dairy cattle. Ovarian cysts are non-ovulated follicles with incomplete luteinization which result in nymphomania or irregular estrus.

Historically, cystic ovaries have responded to an exogenous source of luteinizing hormone (LH) such as human chorionic gonadotropin. Fertagyl ® initiates release of endogenous LH to cause ovulation and luteinization.

Under the provisions of the Federal Food, Drug, and Cosmetic Act, as amended by the Generic Animal Drug and Patent Term Restoration Act, (53 FR 50460, December 15, 1988, First GADPTRA Policy Letter) an abbreviated new animal drug application (ANADA) may be submitted for a generic version of an approved new animal drug (pioneer product). New target animal safety data, drug effectiveness data, and human food safety data (other than tissue residue data) are not required for approval of an ANADA. An ANADA relies on the target animal safety, drug effectiveness, and human food safety data in the pioneer's new animal drug application. Ordinarily, the ANADA sponsor shows that the generic product is bioequivalent to the pioneer. If bioequivalence is demonstrated through a clinical end-point study, then a tissue residue study to establish the withdrawal time for the generic product is also required. For certain dosage forms, the agency will grant a waiver from conducting an in vivo bioequivalence study (55 FR 24645, June 18, 1990; Fifth GADPTRA Policy Letter; Bioequivalence Guideline, April 1990).

Based upon the formulation characteristics of the generic product, Intervet Inc. was granted a waiver from conducting an in vivo bioequivalence study for gonadorelin diacetate tetrahydrate. The generic and pioneer products contain the same active and inactive ingredients and are parenteral solutions.

V. HUMAN FOOD SAFETY:

ToleranceA tolerance has not been established for gonadorelin diacetate tetrahydrate.

Withdrawal TimeWhen a waiver of in vivo bioequivalence testing is granted, the withdrawal times are those previously assigned to the pioneer product. A zero withdrawal is applied to gonadorelin diacetate tetrahydrate.

Regulatory Method for ResiduesSince gonadorelin is approved with a zero withdrawal, an official analytic method is not needed.

VI. AGENCY CONCLUSIONS:

This ANADA submitted under section 512(b) of the Federal Food, Drug, and Cosmetic Act satisfies the requirements of section 512(n) of the act and demonstrates that gonadorelin diacetate tetrahydrate injection when used under the proposed conditions of use, is safe and effective for its labeled indications.

Attachments:The following generic labeling and currently approved pioneer labeling are attached.